Research efforts have been directed towards an elucidation of the structure of the cell wall lipopolysaccharide in Xanthomonas sinensis. A number of oligosaccharides have been isolated from partial acid hydrolysates. A reconstruction of the LPS structure shows that the LPS has an inner "core" composed of mannose, glucose and galacturonamide. The remaining portion of the cell wall LPS appears to be composed solely of rhamnose. Our current studies are directed towards establishing a complete structure of this molecule.